Lavender is a popular Mediterranean shrub, appreciated for its aromatic foliage and vibrant purple flowers. Annual pruning is an important maintenance task that keeps the plant healthy and prevents it from becoming woody and sparse. Pruning ensures a compact, bushy form and abundant blooms, but instructions vary based on the plant’s age and condition.
Timing Your Pruning Cuts
The primary time for significant pruning is immediately after the first main flush of flowers has faded, typically in late summer or early fall. This post-bloom cut removes spent flower spikes and reduces the plant’s size, encouraging new growth for next season’s flowers. This should be done before the plant begins winter dormancy.
A secondary, lighter trim can be performed in early spring as new leaves emerge. This spring cut should focus on removing winter-damaged stems and shaping the plant slightly before the main growing season. Avoid pruning late in the autumn or winter, as fresh cuts stimulate tender new growth highly susceptible to frost damage.
How Far to Cut Established Plants
For established, healthy lavender plants, cut back approximately one-third of the plant’s overall height. This reduction encourages dense foliage, a rounded shape, and promotes good air circulation. The primary guiding principle, often called the “green wood rule,” is to ensure every cut is made into the soft, leafy, green growth of the stem.
Always leave at least one to two inches of green foliage above the woody, brown base. The old, woody stem is often referred to as the “dead zone” because lavender rarely sprouts new foliage from this wood. Cutting into this bare section can leave a permanent, leafless hole or cause the entire branch to die back.
Annual pruning into the green growth maintains the plant’s compact size and prevents the buildup of bare, woody stems. Aim for a symmetrical, domed shape, ensuring the center is slightly higher than the sides to allow sunlight to reach the lower foliage. Removing the top third of the green growth directs the plant’s energy toward developing a strong framework for the following year’s abundant flowering.
Pruning Young Plants and Woody Bushes
Pruning Young Plants
Young lavender plants (first two years) require an approach focused on structure rather than flower production. Prune these plants lightly but frequently through tip pruning, trimming only the soft, growing tips. This regular cutting encourages multiple side shoots, which is essential for developing a dense framework that supports heavy flowering in future years.
Pruning Woody Bushes
Overgrown, neglected lavender bushes that are bare and woody require a renovation pruning strategy. Renovation pruning carries a risk, as cutting deeply into old, leafless wood often prevents regrowth. The safest method is a hard cut in early spring, removing up to 50% of the plant’s height, but only cutting into wood that still shows small signs of green or nodes where new growth might emerge.
For severely woody plants, a less drastic, multi-year approach is recommended to minimize shock. Prune only one-third of the woody stems back by about half in the first year, tackling the remaining sections over the next two seasons. This gradual reduction allows the plant time to recover and encourages new shoots from the remaining sections, rejuvenating the plant’s form.